Adding a Procedural Crater to a Terrain Created by ANT Landscapes
That can be this kind of settings.

What is happening in the nodes shown in the question is &quot;displacement&quot; node is going along the faces normals, and they should go down.
(this issue does not occur in the video tutorial as he uses a flat plane)
So I've used a &quot;vector displacement&quot; that allows to displace along the wanted vector (0, 0, 1).
(the other parts of the node tree is on the same base as yours)